Physics classes

Finding a teacher might seem an easy task but in real life, it isn't. Let's face it, we all have been through the tough time of searching teachers. Some searches turned out to be successfull while others were not so successfull. And there came a point when we ended up thinking- there's got to be an easier way. Right? Today there are websites to find friends, parking spots, used items and what not. So we, a group of teachers, decided to build a platform for it. The result? SYCOS.. SYCOS has been crafted for just one purpose- to connect students with teachers and veice-versa. And that's exactly what we're trying to achieve.

SYCOS- Search Your Companion Of Study.

Search Study Companion "A flower needs a medium to spread its fragrance " Sycos.in provides you that "medium" to spread your fragrance of knowledge and enhance it further. Connect with us and support us by sharing this initiative as well. We request all the students,teachers or coaching institutions to register themselves...

The Largest Black Holes in the Universe
https://youtu.be/xp-8HysWkxw?t=143

The Largest Black Holes in the Universe Our Milky Way may harbor millions of black holes... the ultra dense remnants of dead stars. But now, in the universe far beyond our galaxy, there's evidence ...

see this

In a p–n junction, without an external applied voltage, an equilibrium condition is reached in which a potential difference is formed across the junction. This potential difference is called built-in potential V_{\rm bi}.

After joining p-type and n-type semiconductors, electrons from the n region near the p–n interface tend to diffuse into the p region. As electrons diffuse, they leave positively charged ions (donors) in the n region. Likewise, holes from the p-type region near the p–n interface begin to diffuse into the n-type region, leaving fixed ions (acceptors) with negative charge. The regions nearby the p–n interfaces lose their neutrality and become charged, forming the space charge region or depletion layer (see figure )

The p–n junction possesses some interesting properties that have useful applications in modern electronics. A p-doped semiconductor is relatively conductive. The same is true of an n-doped semiconductor, but the junction between them can become depleted of charge carriers, and hence non-conductive, depending on the relative voltages of the two semiconductor regions. By manipulating this non-conductive layer, p–n junctions are commonly used as diodes: circuit elements that allow a flow of electricity in one direction but not in the other (opposite) direction. Bias is the application of a voltage across a p-n junction; forward bias is in the direction of easy current flow, and reverse bias is in the direction of little or no current flow.

1 Properties of a p–n junction

A p–n junction is a boundary or interface between two types of semiconductor material, p-type and n-type, inside a single crystal of semiconductor. It is created by doping, for example by ion implantation, diffusion of dopants, or by epitaxy (growing a layer of crystal doped with one type of dopant on top of a layer of crystal doped with another type of dopant). If two separate pieces of material were used, this would introduce a grain boundary between the semiconductors that would severely inhibit its utility by scattering the electrons and holes

p–n junctions are elementary "building blocks" of most semiconductor electronic devices such as diodes, transistors, solar cells, LEDs, and integrated circuits; they are the active sites where the electronic action of the device takes place. For example, a common type of transistor, the bipolar junction transistor, consists of two p–n junctions in series, in the form n–p–n or p–n–p.